The present invention relates to novel substituted 6-hydroxy-2,3-dihydrobenzopyran and analogs thereof useful as anti-inflammatory agents.
It has been observed that the novel compounds of this invention are active in vitro in both the peritoneal macrophage assay and the polymorphonuclear leukocyte assay for general anti-inflammatory activity. Specifically, they are found to be active in vivo in the mouse ear assay for topical anti-inflammatory agents. Furthermore, these compounds tend to be inactivated in vivo after deeper and longer penetration into the body system and are therefore devoid of any significant adverse side effects normally associated with systemic activity.
Recent studies demonstrated that macrophages participate in the development and progression of chronic inflammatory diseases such as rheumatoid arthritis. During the progression of inflammatory conditions, there is generally an appearance and/or presence of macrophages and lymphocytes, especially macrophages and polymorphonuclear leukocytes. Macrophages are known to secrete various products in response to inflammatory stimuli. For example:
(1) Neutral proteases--the destructive peptide bond cleaving enzymes which have been shown to be directly involved in rheumatoid cartilage destruction; and PA1 (2) Prostaglandins (PG) (e.g., E.sub.2 and I.sub.2 by mouse peritoneal macrophages) and other arachidonic acid derivatives derived from both the cyclooxygenase and the lipoxygenase pathways.
These arachidonic acid oxygenation products have been identified as the critical mediators of various acute inflammatory conditions.
Accordingly, pharmacological agents which are capable of inhibiting the formation or the release of a mediator and thereby interfere with the function of macrophages or polymorphonuclear leukocytes may also be effective anti-inflammatory agents. For example, nonsteroidal anti-inflammatory drugs such as indomethacin and clinoril are known cyclooxygenase inhibitors. Through their ability to inhibit the formation of prostaglandins, they have been used for rheumatoid arthritis and osteoarthritis. Other inflammatory diseases such as emphysema, bronchial inflammation, acute respiratory distress syndrome, spondylitis, lupus, gout, and psoriasis may also be treated with these pharmacological agents.
Regarding the topical mouse ear assay, it has been previously established that classical nonsteroidal anti-inflammatory agents such as indomethacin and steroidal anti-inflammatory agents such as dexamethasone are active in this assay.
Another object of this invention is to provide appropriate processes for the preparation of the subject novel compounds.
Still a further object of the present invention is to provide a pharmaceutically acceptable composition containing an effective amount of the active compound for the treatment of various inflammatory conditions.
Finally, it is the ultimate object of this invention to develop a method of treating inflammation via the administration of a therapeutically effective amount of the novel compounds or pharmaceutically acceptable composition thereof to a mammalian species in need of such treatment.